Astragalus membranaceous, a perennial grown in Northern China, attains a height of about 20 feet. Substances in its roots stimulate the immune system. A. membranaceous, classified in traditional Chinese medicine as an enhancer of the functions of spleen and lung. It is used not only as a holistic tonic but also for treating edema, reducing excessive perspiration, purging toxins, and promoting tissue healing.
Osteoarthritis (OA), also known as degenerative arthritis, is a type of arthritis characterized by chronic degeneration of the cartilage in the joints, causing severe pain. OA is most commonly found in joints of hands, hips, knees and spine. Development of OA has been attributed to various factors, e.g., age, gender, heredity, stress, and overweight. See David et al., Arthritis & Rheumatism, 1998, 41(8): 1343-1355; BAGGE et al, Age Ageing, 1992; 21: 160-167; Van Saase J L C M, et al., Ann Rheum Dis 1989; 48:271-80. In addition, matrix metalloproteinases (MMPs), a family of zinc-dependent endopeptidases that degrades collagen, have been found to contribute to OA development.
Traditionally, OA is treated with either pain relievers (e.g., aspirin) or nonsteroidal anti-inflammatory drugs (e.g., diclofenac, ibuprofen and naproxen), which are cyclooxygenase inhibitors. Pain relievers only alleviate OA syndromes but do not prevent the development of this disease; nonsteroidal anti-inflammatory drugs, on the other hand, have been found to exhibit various side effects, such as gastrointestinal toxicity and cardiovascular adverse effects. See Manathip et al., Arthritis Care & Research 1999, 12(5): 351-362; Hinz B et al, Nat Clin Pract Rheumatol. 2007 October; 3(10):552-60; quiz 1 p following 589. Thus, there is a need to develop new OA drugs.